class Student(object):
	
	def __init__(self,name,score):
		self.__name = name
		self.__score = score

	# def print_score(self):
	# 	print('%s: %s' % (self.__name, self.__score))

	def get_name(self):
		return self.__name

	def get_score(self):
		return self.__score

	def set_score(self,score):
		if 0 <= score <= 100:
			self.__score = score
		else:
			raise ValueError('bad score')

	def get_grade(self):
		if self.__score >= 90:
			return 'A'
		elif self.__score >= 60:
			return 'B'
		else:
			return 'C'

	# def get_grade(self):
 #        if self.__score >= 90:				
 #            return 'A'
 #        elif self.__score >= 60:
 #            return 'B'
 #        else:
	# 		return 'C'

bart = Student('Bart Simpson',59)
print('bart.get_name()=',bart.get_name())
bart.set_score(60)
print('bart.get_score =', bart.get_score())

print('Do NOT use bart._Student__name:',bart._Student__name)